The Vishay ILD615-4 is a dual-channel transistor-output optocoupler in an 8-DIP through-hole package, rated for 5300 Vrms isolation between input and output.
Isolation and CTR — designing for long-term margin
The 5300 Vrms isolation rating suits applications requiring reinforced insulation per IEC 60950-1 or IEC 60747-5-5, such as isolated power-supply feedback loops or industrial interface circuits. The working voltage at which the isolation holds long-term is lower than the test voltage — budget for the system's continuous working voltage, not the 1-minute hipot value. Current transfer ratio (CTR) is specified between 160% and 320% at a forward current of 10 mA. That 2:1 min-to-max spread covers LED output variation across temperature and over life. The LED fades — CTR degrades by roughly 20-30% over 100,000 hours at rated current — so a design targeting the minimum 160% at end of life needs to start well above that. A 320% max means the output saturates at lower input current, but the real margin question is how much headroom remains after aging.
Output drive and switching speed
Each transistor output can sink up to 50 mA with a maximum collector-emitter voltage of 70 V. Rise and fall times are 2 µs typical each, with turn-on and turn-off times of 3 µs and 2.3 µs respectively. That limits the usable data rate to roughly 100 kbit/s in practice — above that, the output pulse width distortion becomes significant. For faster isolated communication, look at a logic-output or high-speed optocoupler.
The ILD615-4 comes in a standard 8-DIP package (0.300-inch body width, 7.62 mm lead pitch), through-hole mounting. The supplier device package is listed as 8-DIP. It ships in tubes, not tape-and-reel, which is typical for DIP optocouplers — plan for hand-insertion or tube-fed auto-insertion on the line.
Temperature range and deployment context
Rated for -55°C to +100°C operating ambient, the ILD615-4 covers industrial temperature grade with margin on both ends. That makes it suitable for outdoor telecom cabinets, motor-drive control boards, and industrial power supplies where the enclosure sees seasonal extremes.